See below.
> -----Original Message-----
> From: Peter Wallace [mailto:[email protected]]
> Sent: September 17, 2026 3:13 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Ethernet send packets jitter
>
> On Thu, 17 Sep 2026, John Dammeyer wrote:
>
> > I wonder if I'm having the same problem.
> > I have a MESA 7i92H on a PC. I boot, I home all axis. Maybe jog around
a
> bit. Then hit the ESTOP to remove power to the drives, turn off monitor
and
> leave the shop. The PC stays running. A day or two later I come back and
> everything is fine.
> > Or...
> > I get this message as shown in the attached latency.txt file.
> >
> > Unexpected realtime delay on task 0 with period 1000000
> > This Message will only display once per session.
> > Run the Latency Test and resolve before continuing.
> >
> > This error may not show up for days and never really when I'm working
> with the system either running G-code or doing something manually.
>
> If you have a Intel Ethernet chip on your PC do you have irq coalescing
> disabled?
-----------------------------------------------------
Here's what google says I have:
AI Overview
The Lenovo ThinkCentre M57 (Type 9181) is an older business desktop computer
released around 2007 or 2008.
Overview and Specifications
Product Line: ThinkCentre M57 Small or Tower DesktopType Number: 9181
Original Processor: Typically came with Intel Core 2 Duo processors (such
as the E6540 or E6550) or Celeron options.
Memory: Originally shipped with DDR2 RAM (often 1 GB or upgradeable).
The Lenovo ThinkCentre M57 (9181-A1U) is equipped with an integrated Intel
82566DM Gigabit Ethernet Controller.
-----------------------------------------------------
The /etc/network/interfaces file does not have:
iface eth0 inet static
...
hardware-irq-coalesce-rx-usecs 0
It only has the MESA IP and mask.
>
> Do you have isolcpus=N with N set to the last core in you grub file?
Which grub file? The .cfg created from the script?
>
>
> If so do you also have the Ethernet IRQ pinned to the last core?.
Don't know how to do that.
>
I'm thinking maybe I should buy a newer PC and install LinuxCNC 2.9 and
leave 2.8 behind?
> >
> > Suggestions?
> > Thanks
> > John
> >
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
